How to control GPIOs on Pin-Header 2?

#1

Hi,
i’m using RockPiS (hardware v12) and i can control GPIOs on PinHeader 1 without problems using libmraa. Works great.
But i can’t control GPIOs, e.g. GPIO 77 up to 80 (pin 2,4,6,8 on PinHeader 2). I need these GPIOs, too. Can you help?
Many Thanks.

#2

Currently it is not available to control GPIOs on 26-pin Header 2 by using libmraa.

#3

Okay. I understand.
And when i try to use the filesystem like …

cd /sys/class/gpio
sudo echo 78 > export
cd gpio78
sudo chmod 666 /sys/class/gpio/gpio78/direction
sudo echo out > direction
sudo chmod 666 /sys/class/gpio/gpio78/value
sudo echo 1 > value # output high
sudo echo 0 > value # output low

… it has no effect on the Pin4 at Header2, too.
Is there no chance to use GPIOs from Header2?
Thank you.

#4

You can try this. At first, change to superuser, and then use command echo to set direction and value.

For example,

$ sudo su
# echo 78 > /sys/class/gpio/export
# echo out >  /sys/class/gpio/gpio78/direction
# echo 1 > /sys/class/gpio/gpio78/value
# echo 0 > /sys/class/gpio/gpio78/value
#5

the best solution is to use a port-expander (i use a SX1509 with I²C).
That’s working great.

#7

mraa Gpio() function has a raw parameter. If you use raw=True than you can address any GPIO, even on Header2.

1 Like
#8

Got same problem. on PinHeader 2 only work 72(GPIO2_B0) and 80(GPIO2_C0) gpio, other 75,76,77,78,79 not working. I try thru libmraa RAW, SYSFS/CLASS/GPIO, no chance.
Think, some thing in kernel, but chek all rock-p-s dts tree and found no problem. remove support wifi,bluetooth,sound,i2s0_8ch,pdm from dts tree in kernell but same problem. Mb pcb problem ?
Last try … dev/mem

#9

dev/mem no way,
wrote simple kernel driver to test and debug gpios.
not linux kernell driver problem at all.
problem in rk3308 firmware. :frowning:
rk3308 manual

#10

I`m so sorry, my folt.
All work fine.
Finally found my pcb error (easy eda component rock pi s pinheader2 180 degree, do not use it).
I thik that man who draw component in esasy eda open this post :))